Add perlin noise texture

src/main.rs

@@ -2,7 +2,7 @@ use std::sync::{Arc, Mutex};
 use std::time::Instant;
 
 use crate::camera::Camera;
-use crate::hittable::{Hittable, Sphere, HittableList, HittableObject};
+use crate::hittable::{Sphere, HittableList, HittableObject};
 use crate::output::{Output, PNG};
 use crate::ray::Ray;
 use crate::vec3::{Color, Point3, Vec3};
@@ -12,7 +12,8 @@ use rand::distributions::{Distribution, Uniform};
 use rayon::iter::{IntoParallelIterator, ParallelIterator};
 use crate::material::{Dielectric, Lambertian, Material, Metal};
 use crate::aabb::Aabb;
-use crate::bvh::BVH;
+use crate::noise::NoiseTexture;
+use crate::perlin::Perlin;
 use crate::texture::CheckerTexture;
 
 mod vec3;
@@ -24,6 +25,8 @@ mod output;
 mod aabb;
 mod bvh;
 mod texture;
+mod perlin;
+mod noise;
 
 fn two_spheres() -> HittableList {
     let mut world:HittableList = Vec::new();
@@ -43,6 +46,22 @@ fn two_spheres() -> HittableList {
     }));
     world
 }
+fn two_perlin_spheres() -> HittableList {
+    let mut world:HittableList = Vec::new();
+    let noise = NoiseTexture { noise: Perlin::new() };
+    let noise_material = Arc::new(Material::Lambertian(Lambertian::textured(Arc::new(noise))));
+    world.push(Arc::new(Sphere {
+        center: Point3::new(0.0, -1000.0, 0.0),
+        radius: 1000.0,
+        material: Arc::clone(&noise_material)
+    }));
+    world.push(Arc::new(Sphere {
+        center: Point3::new(1.0, 2.0, 1.0),
+        radius: 2.0,
+        material: noise_material
+    }));
+    world
+}
 
 fn random_scene() -> HittableList {
     let mut world: HittableList = Vec::new();
@@ -134,7 +153,7 @@ fn main() {
 
     let look_from = Point3::new(13.0, 2.0, 3.0);
     let look_at = Point3::new(0.0, 0.0, 0.0);
-    let focus_dist = 10.0;
+    let focus_dist = 2.0;
 
     // Camera
     let cam = Camera::new(
@@ -142,16 +161,17 @@ fn main() {
         look_at,
         Vec3::new(0.0, 1.0, 0.0),
         ASPECT_RATIO,
-        40.0,
+        20.0,
         0.0,
         focus_dist,
     0.0,
     1.0);
 
     // World
-    let scene: u8 = 0;
+    let scene: u8 = 1;
     let world = match scene {
         0 => two_spheres(),
+        1 => two_perlin_spheres(),
         _ => random_scene()
     };
 

src/material.rs

@@ -1,4 +1,3 @@
-use std::rc::Rc;
 use std::sync::Arc;
 use rand::Rng;
 use crate::hittable::HitRecord;

src/noise.rs

@@ -0,0 +1,13 @@
+use crate::perlin::Perlin;
+use crate::{Color, Point3};
+use crate::texture::Texture;
+
+pub struct NoiseTexture {
+    pub noise: Perlin
+}
+
+impl Texture for NoiseTexture {
+    fn value(&self, _u: f64, _v: f64, point: &Point3) -> Color {
+        Color::new(1.0, 1.0, 1.0) * self.noise.noise(point)
+    }
+}

src/perlin.rs

@@ -0,0 +1,46 @@
+use rand::distributions::{Distribution, Uniform};
+use rand::Rng;
+use crate::Point3;
+
+pub struct Perlin {
+    ranfloat: Vec<f64>,
+    perm_x: Vec<usize>,
+    perm_y: Vec<usize>,
+    perm_z: Vec<usize>,
+}
+
+impl Perlin {
+    const POINT_COUNT: usize = 256;
+
+    pub fn new() -> Self {
+        let range = Uniform::from(0.0..1.0);
+        let mut rng = rand::thread_rng();
+        let mut ranfloat = Vec::with_capacity(Perlin::POINT_COUNT);
+        (0..Perlin::POINT_COUNT).for_each(|_i|ranfloat.push(range.sample(&mut rng)));
+        Perlin {
+            ranfloat,
+            perm_x: Perlin::perlin_generate_perm(),
+            perm_y: Perlin::perlin_generate_perm(),
+            perm_z: Perlin::perlin_generate_perm(),
+        }
+    }
+
+    pub fn noise(&self, point: &Point3) -> f64 {
+        let i = ((4.0 * point.x()) as i32) & 255;
+        let j = ((4.0 * point.y()) as i32) & 255;
+        let k= ((4.0 * point.z()) as i32) & 255;
+        let idx = self.perm_x[i as usize] ^ self.perm_y[j as usize] ^ self.perm_z[k as usize];
+        self.ranfloat[idx]
+    }
+
+    fn perlin_generate_perm() -> Vec<usize> {
+        let mut p = Vec::with_capacity(Perlin::POINT_COUNT);
+        (0..Perlin::POINT_COUNT).for_each(|i| p.push(i));
+        let mut rng = rand::thread_rng();
+        (1..Perlin::POINT_COUNT).rev().for_each(|idx| {
+            let target = rng.gen_range(0..=idx);
+            p.swap(idx, target);
+        });
+        p
+    }
+}